/*
 * Copyright 2020-2030 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.extraty.question14;

/**
 * @author Created by Neil Wang
 * @version 1.0.0
 * @date 2021/9/1 4:01 下午
 */
public class Solution2 {
    public String longestCommonPrefix(String[] strs) {
        String prefix = strs[0];
        for (int i = 1; i < strs.length; i++) {
            prefix = longestCommonPrefix(strs[i], prefix);
        }
        return prefix;
    }

    private String longestCommonPrefix(String str, String prefix) {
        return str.substring(0, compare(str, prefix));
    }

    private int compare(String str, String prefix) {
        int length = minLength(str, prefix);
        for (int i = 0; i < length; i++) {
            if (str.charAt(i) != prefix.charAt(i)) return i;
        }
        return length;
    }

    private int minLength(String str, String prefix) {
        return Math.min(str.length(), prefix.length());
    }
}
